Method and apparatus for the analysis of a dispersed phase capable of transmitting and focusing light

ABSTRACT

A method and apparatus for the analysis of a dispersed phase capable of transmitting and focusing light in a continuous fluid phase capable of transmitting light wherein a light beam of varying intensity is passed through the dispersed phase contained in the continuous phase whereby the light is focused by the dispersed phase to increase the intensity of light striking a light sensing means to increase the signal of the sensing means and the variation is subtracted from the signal of the sensing means to provide a more discernible difference between signals induced by the presence of the dispersed phase and signals induced by the presence of opaque contaminants.

Unlted States Patent 1191 1111 3,864,044

Lyshkow 1451 Feb. 4, 1975 METHOD AND APPARATUS FOR THE 3,480,369 11/1969Smythe et a1. 356/201 ANALYSIS OF A DISPERSED PHASE 3,609,379 9/1971Hildebrandt 250/218 3,612,887 10/1971 Canevari et al 250/218 CAPABLE OFTRANSMITTING AND 3,617,136 11/1971 Lyshkow 356/206 FOCUSING LIGHT3,705,771 12/1972 Friedman et al 356/208 75 Inventor: Norman A. Lyshkow,Chicago, 111. 3708265 1/1973 Lyshkew 356/208 3,723,737 3/1973 Zeldman250/217 SS [73] Assignee: Combustion Equipment Associates, 3,736,4315/1973 Childs 356/208 Inc., New York, NY. [22] Filed, May 7 1973 PrimaryExaminer-Vincent P. McGraw 1 1 pp 357,901 57 ABSTRACT Related US.Application Data A method and apparatus for the analysis of a dis- [63]Continuation-impart of Ser. No. 309,644, Nov. 27, persed phase Capableof transmlmng and focusmg 972 abandone light in a continuous fluid phasecapable of transmitting light wherein a light beam of varying intensityis [52] U.S. c1. 356/201, 250/573 passed through the dispersed phasecontained in the [51] Int. (:1. G0ln 21/22 continuous phase whereby thelight is focused by the [58] Fi ld f S h 250K218, 218 X, 217 SS,dispersed phase to increase the intensity of light strik- 25()/573 57 3512 201 205 20 207 ing a light sensing means to increase the signal ofthe 208, 102, 103, 104 sensing means and the variation is subtractedfrom the signal of the sensing means to provide a more discern- [56]References Cit d ible difference between signals induced by the pres-UNITED STATES PATENTS ence of the dispersed phase and signals induced bythe 1,724,870 8/1929 Belt 356/128 presence of Opaque contammams'3,462,608 8/1969 Weston et a1 250/218 31 Claims, 6 Drawing Figures 18112.2 I L1GHT srusonkz LiGHT SOURCE AMPLIFIER 1 FILTER OUTPUT PAIENTED3.864.044

SHEET 10F 2 3-4;; LIGHTSOURCE I I 02 INPUT AMPLIFIER FILTER OUTPUT lINTI-m W 'NPUT QE LIQ HT- SOURCE v ac INPUT LIGHT SENfiOR SIGNAL VOLTAGESIGNAL VOLTAGE AFTER FI LT ER PATENTEDFEB 4I9I5 SHEET 2 OF 2 LIGHTSOURCE SIQHtIL I LIGHT SENSOR AMPLIFIER FILTER Fl G; 6

LIGHT SENSOR AMPLIFIER FILTER Negafiva I Pulses Posvtwe Pulses COUNTERVIBRATOR 1 METHOD AND APPARATUS FOR THE ANALYSIS OF A DISPERSED PHASECAPABLE OF TRANSMITTING AND FOCUSING LIGHT This application is acontinuation-in-part of copending application Ser. No. 309,644, filedNov. 27, I972, and now abandoned.

This invention relates to an improved method and apparatus for theanalysis of liquid systems, and more particularly to a method andapparatus for the analysis of a liquid dispersed in another liquid whichis immiscible with the dispersed liquid.

A number of analytical techniques have been employed in the analysis ofliquid systems formed of droplets or globules of a liquid dispersed in acontinuous phase of another immiscible liquid. A typical liquid systemof this type is an oil-in-water system in which the oil is dispersedthroughout the water in the form of fine droplets or globules generallyhaving a spherical configuration. Analysis of such systems is usuallycarried out with UV absorption or light scattering techniques.

However, such techniques have not been altogether satisfactory for theyrequire costly and complex analytical apparatus. Even with such complexequipment, the precision of such analytical techniques is quite limited.

In my copending application Ser. No. 309,644, filed Nov. 27, 1972, andnow abandoned, there is described an improved method and apparatus forthe annalysis of fluid systems containing droplets or globules of aliquid dispersed in the continuous phase of another liquid in which alight beam is passed through the continuous phase containing thedroplets whereby the droplets exert a lens effect to focus the lightbeam on a light sensor. Each time the light beam passes through adroplet or globule, the intensity of light falling upon the sensor isincreased to thereby provide an increased signal from the light sensor.The frequency of the increased signals or pulses from the light sensorthus serves to indicate the number of droplets present in the continuousphase and consequently the relative amount of the dispersed liquidcontained in the continuous phase.

While the invention disclosed and claimed in the above applicationrepresents a significant advance in the art, the presence ofcontaminants which do not transmit light in the continuous phase effectsthe accuracy of the analysis. This effect can be reduced somewhat by afeedback from the light sensor to the light source as described in theabove application. However, it is frequently quite difficult to detectthe positive pulses resulting from the presense of the dispersedphase'because of their small amplitude and to distinguish between thepositive signal of the light source caused by the presence of a dropletand the negative signal caused by the presence of dirt particles whichinterrupt the light beam.

It is accordingly an object of the present invention to provide animproved method and apparatus for the analysis of a liquid dispersed inan immiscible liquid which overcomes the foregoing disadvantages and iscapable of providing reliable analytical data even when the liquidsystem contains contaminants opaque to light.

It is a more specific object of the invention to provide a method andapparatus for the analysis of a liquid dispersed in an immiscible liquidin which the signal caused by the presence of the dispersed liquid ismore clearly discernible from the signal caused by the presence ofcontaminants which do not transmit light.

It is a further object of the invention to provide a method andapparatus for the analysis of a liquid dispersed in an immiscible liquidin which a light beam is based through a fiber optics system for passagethrough the immiscible liquid containing the dispersed phase and thelight beam is received by a fiber optics system for passage to alightreceiving means to detect increases in light intensity as the light beamis focused by the dispersed phase.

These and other objects and advantages of the invention will appear morefully hereinafter and, for purposes of illustration but not oflimitation, embodiments of the invention are shown in the accompanyingdrawings in which:

FIG. 1 is a schematic illustration of the apparatus of the presentinvention;

FIG. 2 is a graph of the input voltage to the light source shown in FIG.1 with time;

FIG. 3 is a graph of the output voltage of the light sensor of FIG. 1with time;

FIG. 4 is a graph of the output voltage of the filter of FIG. 1 withtime;

FIG. 5 is a schematic illustration of an alternative embodiment of theapparatus of FIG. 1; and

FIG. 6 is a schematic diagram of means to correct the analysis as aresult of contamination.

The concepts of the present invention reside in the discovery that, whena light beam is passed through a continuous fluid phase containing adispersed fluid immiscible with the continuous phase which is capable oftransmitting and focusing a beam of light and contain- .ing contaminantswhich are at least opaque to light, the

positive pulses of increased light intensity are more readilydiscernible from negative pulses of increased light intensity where theintensity of the light beam passed through the continous phase is variedand the resulting signal from the light sensor or sensing means isfiltered to remove the variation intensity. In addition to providing amore clearly discernible difference between such negative and positivepulses as described, the concept of varying the intensity of the lightbeam likewise provides a signal in which problems of drift and DCcoupling are substantially eliminated.

In the preferred practice of the invention, the light source employed isa light emitting diode which is energized with an encoded signal, suchas an AC signal, a saw-tooth signal or a square-wave signal superimposedupon a DC signal to thereby provide a source of light in which theintensity of light varies in accordance with the encoded signal withtime. In general, the effective voltage of the encoded signalsuperimposed upon the DC signal is small in magnitude compared to themagnitude of the DC signal. While not critical to the practice of theinvention, it has been found that best results are usually achieved whenthe effective voltage of the encoded signal is from two to 50 andpreferably five to 15 times the expected increase in light intensity dueto the presence of the dispersed phase in the continuous phase.

Similarly, while not critical to the practice of the invention, bestresults are obtained where the frequency ofthe encoded signal rangesfrom 1/5 to H50, and preferably N15 to 1/30, times the frequency ofglobules or droplets of the dispersed phase. By way of illustration, ithas been found that a DC signal of about 8 volts effective and an ACsignal of about 100 millivolts effective and about 60 cps provide goodresults in the analysis of oil-in-water dispersions.

Referring now to the drawings for a more detailed description of theinvention, there is shown in FIG. 1 a

schematic illustration of the apparatus of the invention which is of thesame general type as that disclosed and claimed in my copendingapplication referred to above. As will be appreciated by those skilledin the art, the dimensions of the drawings have been significantlyenlarged to illustrate the details of the apparatus. The apparatusincludes passage means or chamber through which the dispersion can bepassed. A light source 12 is positioned adjacent to the chamber means 10to pass a wide-beam of light through a wide slit l4 and'through thetransparent chamber 10. Any source of light can be used in the practiceof this invention, including an incandescent lamp, a laser, a lightemitting diode or the like.

Light sensing means 16 is positioned to receive the light passed throughthe chamber 10. The light sensing means 16 can be any of a number oflight sensitive components capable of measuring or detecting adifference intensity of a beamof light, such as a phototransistor, aphotomultiplier tube, a photocell or the like. Interposed between thelight sensing means 16 and the chamber 10 is a light sheld 17 having anarrow slit 18 therein, with the slit 18 being aligned with the lightsensing means 16, the wide slit l4 and the light source 12.

Where the light beam emanating from the light source 12 passes throughthe continuous phase of the dispersion contained in the chamber 10, thelight beam is at least partially shielded from the light sensing means15 by way of the shield 17,-with only a portion of the light passingthrough the slit 18 to strike the light sensing means 16. At this time,the signal or output of the light sensing means 16 substantiallycorresponds to the input signal of the light source 12. However, when adiscrete droplet of the dispersed liquid passes through the beam oflight, the droplet serves as a convex lens to focus the light beam ontothe light sensing means 16, and thereby subject the light sensing means16 to light of greater intensity to increase the signal of the lightsensing means 16 to detect the presence of the droplet 20.

The relative dimensions of the wide slit 14 or breadth of the light beamfrom the light source 12 with respect to the width of the narrow slit 18is not critical to the practice of the invention. It is generallysufficient that the narrow slit 18 be sufficiently small to provide ameasurable difference in light intensity of the focused beam of light,that is the intensity of the beam as it is focused on the light sensingmeans 16 by a droplet of the dispersed liquid, as compared to the lightintensity of the light beam passing through the continuous phase.

It is also preferred in the practice of the invention to space the lightsensing means by a distance sufficient that the distance between adroplet in the chamber and the light sensing means is less than thefocal length of the droplet. In this way, a maximum difference betweenthe focused beam of light as compared to the nonfocused beam of light isassured.

In the practice of this invention, the apparatus is provided with meansto energize the light source 12 including means to provide a sourceoflight of constant intensity and means to provide light, superimposedon the light of constant intensity, whose intensity varies with time. Inthe embodiment shown in FIG. I of the drawing, the light source 12 ispreferably a light emitting diode which is energized by a source 22 ofDC voltage and a source 24 of AC voltage.

The intensity ofthe light emitted from light source 12 is showngraphically in FIG. 2 of the drawing. As illustrated, the light emittedas a result of the DC excitation is constant with time. Superimposedupon the light of constant intensity is light emitted as a result of theAC excitation of the light emitting diode whose intensity variessinusoidally with time.

The light beam having the characteristics illustrated in FIG. 2 of thedrawing is passed through the chamber 10 as described above, and when adroplet or globule of the dispersed phase passes through the chamber 10,the light beam is focused onto the light sensor 16 to provide anincrease or pulse in the intensity of the light illuminating the sensor16. Similarly, when a particle of a contaminant materiaL'which is atleast opaque to light, passes through the chamber, the light beam is atleast partially interrupted by the particle, thereby resulting in adecrease or negative pulse in the intensity of the light illuminatingthe light sensing means 16.

As will be appreciated by those skilled in the art, the signal from thelight sensing means reflects the variation in the light illuminating thesensing means 16; the

signal from thelight sensing means is shown in FIG. 3 of the drawing.The sine wave reflects the sinusoidally varying light emitted from thelight source 12, and the positive pulses 26 detected result from thedispersed phase serving to focus thelight beam to increase the intensityof light incident on the sensing means 16 whereas the negative pulses,28 result from the lightopaque contaminant particles serving to decreasethe intensity of light incident upon the light sensing means 16.

The signal from the lightsensing means 16 can then be amplified by meansof a suitable amplifier 30 provided in the system. Amplification of thevarying signal from the sensing means 16 permits'detection of bothpositive and negative pulses which are otherwise quite small inmagnitude relative to the magnitude of theDC voltage and consequentlydifficult to detect absent identification.

The amplified signal from the amplifier means 30 is then processed bypassing the signal to a filter 32 or the like means to subtract thevarying signal introduced by the excitation of the light source 12. Thefilter 32 thus serves to substract the sinusoidal variation from thesignal from the amplifier, leaving only the amplified positive pulsesestablished by the dispersed phase and the negative pulses establishedby the contaminant particles present in the continuous phase.

The signal, after subtraction of the encoded signal, is represented bythe graph of FIG. 4. As can be seen from this figure, the signal has asubstantially constant value corresponding to the DC signal input to thelight source 12, with the amplified positive and negative pulses 26 and28, respectively, indicating the presence of the dispersed phase and theopaque contaminant, respectively. The resulting signal can be, ifdesired, amplified by suitable amplifier means 32 without the problemsof drift and DC coupling to provide greater reliability in reading outanalytical data from the electronic signal.

As will be appreciated by those skilled in the art, the filter means tosubtract the varying signal can be any of the filters well-known tothose skilled in the art. For example, use can be made of high passturned filters for this purpose.

While the invention has been described above with reference to anencoded signal in the form of an AC signal superimposed on the DC signalto the light source, the invention contemplates the use of other encodedsignals which vary in magnitude and/orfrequency with time-As indicatedabove, use can be made of an encoded signal in the form of a saw toothsignal or a square wave signal.

Another embodiment of the invention is shown in FIG. Sof the drawing.The apparatus of this embodiment is similar to that shown in FIG. 1 ofthe drawing, and the same elements are designated by the same referencenumerals. However, instead of having the light source 12 and the lightsensing means 16 in alignment with the slits l4 and 18, the light beamis transmitted through fiber optics means 34 for passage through thechamber and the light beam passing through the chamber 10 is receivedbysecond fiber optics means 36 for transmission therethrough to the lightsensing means. By the use of such fiber optics systems, it is possibleto pass the light beam to and from the chamber 10' through a curved pathand consequently reduce the size of the overall apparatus. The use offiber optics means as described and shown in the drawings obviates theneed to employ slits of the type used in FIG. 1 since thecross-sectional area of the fiber optics means 34 is dimensioned to begreater than that of the fiber optics means 36 to assure the desiredmeasurable difference in intensity of the light illuminating fiberoptics means 36 when a droplet or globule of the dispersed phaseintercepts the light beam from fiber optics means 34 to fiber opticsmeans 36.

As is now well known to those skilled in the art, such fiber opticssystems, which are commercially available, are generally formed of abundle of glass or plastic fibers which are capable of transmittinglight over their entire lengths. Because the bundle is formed of aplurality of individual fibers, the bundle is flexible and is capable ofconducting light through a curved path.

In the preferred embodiment of the invention, the apparatus is includedwith means to compensate for error in analysis due to the presence ofcontaminant material which is opaque to light in the continuous phase.As those skilled in the art will appreciate, the apparatus of theinvention is incapable of detecting a droplet or globule of thedispersed phase present in the light beam when a light-opaque particleis likewise in the light beam. To correct for such errors in detectionand analysis, the apparatus can include a monostable multivibratoroperatively connected to, for example, the filter as shown in FIG. 6 ofthe drawing. Negative pulses constituting a portion of the signal fromthe filter are pulses through the vibrator, and positive pulses aresupplied to counting means 40. The negative pulses are thus converted toa pulse of greater time duration by the vi brator, and the latter arecounted by the counting means 40 to correct the number of positivepulses for the period in which the positive pulses cannot be counted dueto the presence of the contaminant.

In the practice of this invention, a mixture of the immiscible liquidsis just homogenized to insure that a substantially complete dispersionis obtained. The formation and stability of the dispersion canfrequently be enhanced by carrying out the homogenization in thepresence of a surfactant. Thereafter, the dispersion is placed in and/orpassed through the chamber and the positive pulses or the light sensingmeans are counted as an indication of the number of droplets of thedispersed liquid contained in the continuous phase.

The concepts of the invention are applicable to systems of immiscibleliquids which are capable of trans mitting light and which contain oneliquid dispersed as droplets or globules in another fluid as acontinuous phase. It has been found that the present invention isparticularly well suited for use in the analysis of oil-inwateremulsions and water-in-oil emulsions. As will be appreciated by thoseskilled in the art, the concepts of the invention are also applicable todispersions of balls of solids which arecapable of transmitting andfocusing light dispersed in a fluid continuous phase.

It will be understood that various changes and modifications can be madein the details of construction, procedure and use without departing fromthe spirit of theinvention, especially as defined in the followingclaims.

I claim:

1. Apparatus for analysis of a dispersed phase capable of transmittingand focusing light contained in a continuous phase capable oftransmitting light, comprising chamber means adapted to contain thedispersed phase and the continuous phase, a light source positioned topass a wide beam of light through the chamber means, means associatedwith the light source to generate the light beam with a component ofvarying intensity, light sensing means adapted to detect differences inlight intensity positioned to receive a portion of the light beam passedthrough the chamber means whereby the dispersed phase is passed throughthe beam of light to focus the beam of light onto the light sensingmeans to cause an increase in the intensity of the light beam strikingthe light sensing means to activate the light sensing means for eachdispersed phase in the continuous phase.

2. Apparatus as defined in claim 1 wherein the light sensing meansincludes a light shield interposed between the light sensing means andthe chamber means, said light shield having a narrow'slit thereinadapted to pass a portion of the light beam therethrough.

3. Apparatus as defined in claim 1 wherein the light source includes alight shield having a wide slit therein adapted to define the beam oflight.

4. Apparatus as defined in claim 2 wherein the narrow slit isdimensioned to pass the beam of light therethrough having an intensitymeasurable less than the intensity of the beam focused by the dispersedphase.

5. Apparatus as defined in claim 1 wherein the light sensing means ispositioned from the dispersed phase in the chamber means by a distanceless than the focal length of the dispersed phase.

6. Apparatus as defined in claim 1 wherein the means associated with thelight source includes means to energize the light source to providelight having a relatively constant intensity and means to energize thelight source to provide light of varying intensity whereby the lightbeam is composed of the light of relatively constant intensity on whichthe light of varying intensity is superimposed.

7. Apparatus as defined in claim 6 wherein the means to energize thelight source to provide light of varying intensity is means to generatelight having sinusoidally varying intensity.

8. Apparatus as defined in claim 6 wherein the means to energize thelight source to provide light of varying intensity is means to, generatelight having intensity varying as a square wave.

9. Apparatus as definedin claim 6 wherein the means to energize thelight source to provide light of varying intensity is means to generatelight having intensity varying as a sawtooth wave.

10. Apparatus as defined in claim 1 wherein the light source is a lightemitting dioide and the means associated with the light source includesmeans for providing a DC signal and means for providing a signal ofvarying intensity superimposed on the DC signal.

11. Apparatus as defined in claim 10 wherein the signal of varyingintensity is an encoded signal.

12. Apparatus as defined in claim 1 which includes means to amplify thesignal from the light sensing means.

13. Apparatus as defined in claim 12 which includes filter means tosubtract a signal of varying intensity corresponding to the light ofvarying intensity of the light beam to leave a signal corresponding toincreases in intensity of the light striking the light sensing means anddecreases in intensity of the light striking the light sensing means dueto presence of opaque contaminants.

14. Apparatus as defined in claim 13 which includes vibrator meansadaptedto pulse negative signals from the filter means to correct thenumber of increases in intensity of lightduring presence of contaminantsin the continuous phase.

15. Apparatus as defined in claim 1 which includes first fiber opticsmeans to conduct the light beam to the chamber means for transmissiontherethrough.

16. Apparatus as defined in claim 1 which includes second fiber opticsmeans to conduct light transmitted through the chamber means to thelight sensing means.

17. Apparatus for a dispersed phase capable of transmitting and focusinglight contained in a continuous fluid phase capable of transmittinglight comprising chamber means adapted to contain the dispersed phasecontained in the continuous phase, a light source adapted to-emit a beamof light, first fiber optics means to conduct the beam of light emittedfrom the light source to the chamber means for passage of the beam oflight through the chamber means, light sensing means adapted to detectdifferences in light intensity, second fiber optics means positioned toreceive the light beam passed through the chamber means and to conductthe light beam transmitted through the chamber means to the lightsensing means whereby the dispersed phase is passed through the beam oflight to focus the beam of light onto the light sensing means to causean increase in light intensity of the light beam striking the lightsensing means to activate the'light sensing means for each dispersedphase in the continuous phase.

18. Apparatus as defined in claim 17 which includes means associatedwith the light source to provide the light beam with a component ofvarying intensity.

19. Apparatus as defined in claim 17 wherein the light source is a lightemitting diode and the means associated with the light source includesmeans for providing a DC signal and means for providing a signal ofvarying intensity superimposed on the DC signal.

20. Apparatus as defined in claim 19 wherein the signal of varyingintensity is an encoded signal.

21. Apparatus as defined in claim 17 which includes means to amplify thesignal from the light sensing means.

22. Apparatus as defined in claim 21 which includes filter means tosubtract a signal of varying intensity corresponding to the light ofvarying intensity of the light beam to leave a signal corresponding toincreases in intensity of the light striking the light sensing means anddecreases in intensity of the light striking the light sensing means dueto presence of opaque contaminants.

23. Apparatus as defined in claim 22 which includes vibrator meansadapted to pulse negative signal from the filter means to correct thenumber of increases in intensity of light during presence ofcontaminants in the continuous phase.

24. Apparatus as defined in claim 17 wherein the first fiber opticsmeans has a greater cross-sectional area than the second fiber opticsmeans.

25. Apparatus as defined in claim 24 wherein the second fiber opticsmeans is dimensioned to pass the beam of light therethrough having anintensity measurably less than the intensity of the beam focused by thedis persed phase.

26. In an apparatus for the analysis of a dispersed phase capable oftransmitting and focusing light in a continuous fluid phase whichincludes chamber means adapted to contain the dispersed phase containedin the continuous phase, a light source positioned to pass a wide beamof light through the chamber means, light sensing means adapted todetect differences in light intensity positioned to receive a portion ofthe light beam passed through the chamber means whereby the dispersedphase is passed through the beam of light to focus the beam of lightonto the light sensing means to cause an increase in the intensity ofthe light beam striking the light sensing means, the improvementcomprising at least one fiber optics means to conduct light between atleast one of the light sensing means and the light source, and thechamber means.

27. Apparatus as defined in claim 26 which includes means associatedwith the light source to provide the light beam with a component ofvarying intensity.

28. A method for measuring a discrete dispersed phase capable oftransmitting and focusing light contained in a continuous fluid phasecomprising the steps of passing the dispersed phase contained in thecontinuous phase through a transparent zone, passing a broad beam oflight having a component which varies in intensity whereby the beam oflight is focused by discrete portions of the dispersed phase to provideimpulses of light of increased intensity as compared to the intensity ofsaid beam, converting the impulse to an electrical signal, amplifyingthe signal and subtracting the portion of the signal corresponding tosaid light varying intensity.

29. A method as defined in claim 28 wherein the dispersed phase is awater-immiscible oil and the continuous phase is an aqueous mediumimmiscible with the oil.

30. A method as defined in claim 28 which includes the step ofhomogenizing the dispersed phase in the presence of the continuous phaseto form discrete droplets of the dispersed phase in the continuousphase.

31. A method as defined in claim 30 wherein the homogenizing is carriedout in the presence of a surfactant to promote the formation of dropletsof the dispersed phase in the continuous phase.

1. Apparatus for analysis of a dispersed phase capable of transmittingand focusing light contained in a continuous phase capable oftransmitting light, comprising chamber means adapted to contain thedispersed phase and the continuous phase, a light source positioned topass a wide beam of light through the chamber means, means associatedwith the light source to generate the light beam with a component ofvarying intensity, light sensing means adapted to detect differences inlight intensity positioned to receive a portion of the light beam passedthrough the chamber means whereby the dispersed phase is passed throughthe beam of light to focus the beam of light onto the light sensingmeans to cause an increase in the intensity of the light beam strikingthe light sensing means to activate the light sensing means for eachdispersed phase in the continuous phase.
 2. Apparatus as defined inclaim 1 wherein the light sensing means includes a light shieldinterposed between the light sensing means and the chamber means, saidlight shield having a narrow slit therein adapted to pass a portion ofthe light beam therethrough.
 3. Apparatus as defined in claim 1 whereinthe light source includes a light shield having a wide slit thereinadapted to define the beam of light.
 4. Apparatus as defined in claim 2wherein the narrow slit is dimensioned to pass the beam of lighttherethrough having an intensity measurable less than the intensity ofthe beam focused by the dispersed phase.
 5. Apparatus as defined inclaim 1 wherein the light sensing means is positioned from the dispersedphase in the chamber means by a distance less than the focal length ofthe dispersed phase.
 6. Apparatus as defined in claim 1 wherein themeans associated with the light source includes means to energize thelight source to provide light having a relatively constant intensity andmeans to energize the light source to provide light of varying intensitywhereby the light beam is composed of the light of relatively constantintensity on which the light of varying intensity is superimposed. 7.Apparatus as defined in claim 6 wherein the means to energize the lightsource to provide light of varying intensity is means to generate lighthaving sinusoidally varying intensity.
 8. Apparatus as defined in claim6 wherein the means to energize the light source to provide light ofvarying intensity is means to generate light having intensity varying asa square wave.
 9. Apparatus as defined in claim 6 wherein the means toenergize the light source to provide light of varying intensity is meansto generate light having intensity varying as a sawtooth wave. 10.Apparatus as defined in claim 1 wherein the light source is a lightemitting dioide and the means associated with the light source includesmeans for providing a DC signal and means for providing a signal ofvarying intensity superimposed on the DC signal.
 11. Apparatus asdefined in claim 10 wherein the signal of varying intensity is anencoded signal.
 12. Apparatus as defined in claim 1 which includes meansto amplify the signal from the light sensing means.
 13. Apparatus asdefined in claim 12 which includes filter means to subtract a signal ofvarying intensity corresponding to the light of varying intensity of thelight beam to leave a signal corresponding to increases in intensity ofthe light striking the light sensing means and decreases in intensity ofthe light striking the light sensing means due to presence of opaquecontaminants.
 14. Apparatus as defined in claim 13 which includesvibrator means adapted to pulse negative signals from the filter meansto correct the number of increases in intensity of light during presenceof contaminants in the continuous phase.
 15. Apparatus as defined inclaim 1 which includes first fiber optics means to conduct the lightbeam to the chamber means for transmission therethrough.
 16. Apparatusas defined in claim 1 which includes second fiber optics means toconduct light transmitted through the chamber means to the light sensingmeans.
 17. Apparatus for a dispersed phase capable of transmitting andfocusing light contained in a continuous fluid phase capable oftransmitting light comprising chamber means adapted to contain thedispersed phase contained in the continuous phase, a light sourceadapted to emit a beam of light, first fiber optics means to conduct thebeam of light emitted from the light source to the chamber means forpassage of the beam of light through the chamber means, light sensingmeans adapted to detect differences in light intensity, second fiberoptics means positioned to receive the light beam passed through thechamber means and to conduct the light beam transmitted through thechamber means to the light sensing means whereby the dispersed phase ispassed through the beam of light to focus the beam of light onto thelight sensing means to cause an increase in light intensity of the lightbeam striking the light sensing means to activate the light sensingmeans for each dispersed phase in the continuous phase.
 18. Apparatus asdefined in claim 17 which includes means associated with the lightsource to provide the light beam with a component of varying intensity.19. Apparatus as defined in claim 17 wherein the light source is a lightemitting diode and the means associated with the light source includesmeans for providing a DC signal and means for providing a signal ofvarying intensity superimposed on the DC signal.
 20. Apparatus asdefined in claim 19 wherein the signal of varying intensity is anencoded signal.
 21. Apparatus as defined in claim 17 which includesmeans to amplify the signal from the light sensing means.
 22. Apparatusas defined in claim 21 which includes filter means to subtract a signalof varying intensity corresponding to the light of varying intensity ofthe light beam to leave a signal corresponding to increases in intensityof the light striking the light sensing means and decreases in intensityof the light striking the light sensing means due to presence of opaquecontaminants.
 23. Apparatus as defined in claim 22 which includesvibrator means adapted to pulse negative signal from the filter means tocorrect the number of increases in intensity of light during presence ofcontaminants in the continuous phase.
 24. Apparatus as defined in claim17 wherein the first fiber optics means has a greater cross-sectionalarea than the second fiber optics means.
 25. Apparatus as defined inclaim 24 wherein the second fiber optics means is dimensioned to passthe beam of light therethrough having an intensity measurably less thanthe intensity of the beam focused by the dispersed phase.
 26. In anapparatus for the analysis of a dispersed phase capable of transmittingand focusing light in a continuous fluid phase which includes chambermeans adapted to contain the dispersed phase contained in the continuousphase, a light source positioned to pass a wide beam of light throughthe chamber means, light sensing means adapted to detect differences inlight intensity positioned to receive a portion of the light beam passedthrough the chamber means whereby the dispersed phase is passed throughthe beam of light to focus the beam of light onto the light sensingmeans to cause an increase in the intensity of the light beam strikingthe light sensing means, the improvement comprising at least one fiberoptics means to conduct light between at least one of the light sensingmeans and the light source, and the chamber means.
 27. Apparatus asdefined in claim 26 which includes means associated with the lightsource to provide the light beam with a component of varying intensity.28. A method for measuring a discrete dispersed phase capable oftransmitting and focusing light contained in a continuous fluid phasecomprising the steps of passing the dispersed phase contained in thecontiNuous phase through a transparent zone, passing a broad beam oflight having a component which varies in intensity whereby the beam oflight is focused by discrete portions of the dispersed phase to provideimpulses of light of increased intensity as compared to the intensity ofsaid beam, converting the impulse to an electrical signal, amplifyingthe signal and subtracting the portion of the signal corresponding tosaid light varying intensity.
 29. A method as defined in claim 28wherein the dispersed phase is a water-immiscible oil and the continuousphase is an aqueous medium immiscible with the oil.
 30. A method asdefined in claim 28 which includes the step of homogenizing thedispersed phase in the presence of the continuous phase to form discretedroplets of the dispersed phase in the continuous phase.
 31. A method asdefined in claim 30 wherein the homogenizing is carried out in thepresence of a surfactant to promote the formation of droplets of thedispersed phase in the continuous phase.